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Background:With the advent of the formaldehyde standard law in France, and because of the impact of new methods for diagnosis and prognosis in pathology, formalin replacement in surgical pathology laboratories is currently being discussed in France. However, a set of criteria must be assessed before introducing a formalin substitute fixative. The objective of this study was to compare formalin substitute fixation with formalin fixation and cryoconservation of tissues from several benign and malignant thyroid pathologies with respect to morphology, antigenicity, and nucleic acid (RNA, DNA, microRNA) integrity.Methods:Calibrated specimens (200 mg, 1 cm2each) from four conventional papillary thyroid carcinomas, four follicular variant of papillary thyroid carcinomas, three minimally invasive follicular carcinomas, four thyroid adenomas, five thyroid nodular hyperplasias, and five normal thyroid tissues were fixed for 6, 12, or 24 hours, in different fixatives (formalin, Glyo-Fixx, FineFIX, ExcellPlus, RCL2) at room temperature or at 4°C. Tissues were stained (hematoxylin–eosin, periodic acid Schiff, trichromic Masson, and Sweet-Gordon staining) and their antigenicity determined by immunohistochemistry (performed with HBME-1, galectin-3, CK19, vimentin, CD31, and KL1 antibodies). Evaluation by four pathologists was made blinded. The quantity and quality of DNA, RNA, and two representative microRNA extracted from deparaffinized sections of paraffin embedded specimen were compared with that of cryosections.Results:The staining and morphology were not altered by the use of different fixatives. However, formalin, FineFIX, and RCL2 gave the best results for immunohistochemistry. Moreover, FineFIX and RCL2 gave the highest amount of nucleic acids and of the best quality.Conclusions:All the formalin substitute fixatives used in this study provided good histomorphologic quality for the different stained thyroid tissues, but individually, some fixatives performed better for immunohistochemical and molecular biological procedures for different thyroid pathologies. [ABSTRACT FROM AUTHOR]

AbstractObjective??In recent years, video-assisted thoracoscopic microdiscectomy has gained acceptance as a minimally invasive, safe, and efficient technique suited for herniated thoracic discs from T4T5 until T11T12. However, correct localization is difficult and wrong level exploration is an ever-present threat. We present a reliable and time-efficient localizing technique.Materials and methods??In 86 consecutive cases, 1?day preoperatively intrathecal contrast was administered and a computed tomography (CT) scan was performed in prone position. Using local anesthesia, a hollow needle was advanced above the corresponding rib and through the pleura. The inner wire and corresponding pathological level were easily identified endoscopically.Conclusion??Myelo-CT provides detailed anatomical information, which is often helpful in determining the side of operative approach and the extent of bone removal needed. Needle localization obviates fluoroscopy, saves OR time, and allows the surgeon to focus on the technically demanding procedure. Furthermore, it is a relatively simple and safe technique. [ABSTRACT FROM AUTHOR]